First off if you own a 2000 Echo LIMITED then i would like to hear about it! As far as i know ALL ECHOS came in the stripped down anti-luxury version that many of us have come to love.
Ours has 135k trouble free miles. It is no longer our main car anymore but it's still an everyday car that we use for business and running errands can't beat the 30+ mpg!.
Well today i purchased a new battery and put the new battery back in the car EXACTLY the same way the old one was placed. That is the terminals were on the same side and the battery caps - (whatever they are called - covers for water reservoirs) were situated the same as the battery that was taken out. Since these are both the same brand/type battery i guess i assumed that everything was the same.
So i hooked up the negative then when i started to hook up the positive i got a few minor sparks when i put it on but thought it was normal. Well as i was tightening the positive terminal down i looked down and saw the negative sign next to the terminal i was attempting to tighten


Actually they were exactly the same battery except the battery terminals and water covers sat on OPPOSITE sides of the battery! The old had the terminals situated on the top right side w/ caps on the left and the new had the reverse.
Car started w/ no problem and got me home but there were no lights, nothing worked on the dash, no a/c, no speedometer, no nothing electrical. Took apart the positive wire fuse case and saw an in line fuse was broken to the alternator. Went to autozone picked up a universal 14gauge in line fuse (will this be ok to use or do need to go to toyota and get factory part?) and when installed the car started up and was back on the road again - seemingly w/ no problems w/ everything working but the radio. From online research learned there is a 15amp fuse in the fuse box for the radio which i am hoping will fix the radio problem.
Then on the way down the highway the temperature light started flashing but I kept driving to my destination. When got back in the car the light didn't come on but on way home it lit back up and started flashing again. Other then the light flashing the car was running fine and later on running a few short errands around town the light didn't come on again - it only came on after driving down the highway after about 10-15 minutes.
Any ideas what might be causing this as a result of crossing the battery wires ?
Could it be something called a coolant temp switch circuit?
Are there any other things i need to be on the lookout for after crossing the battery wires like this?
Thanks much!